: Hydatid disease is a parasitic infestation of humans caused by ECHINOCOCCUS GRANULOSUS. Echinococcus infection is commonly seen in humans. Dogs and some wild carnivores like foxes are definitive hosts, harbouring worms in their intestine. Eggs are passed in the faeces and eaten by the intermediate hosts, and larvae encyst in the liver, lungs and other organs. One of the most frequent reason of the liver mass is hydatid cyst in tropical and rural countries. The most effected organ is liver (75%) and lung (15%) . Other rare seen anatomical locations are brain, breast, heart, spleen, bone, spleen, abdominal wall. Clinical symptoms are varied according to the size, anatomic location and stage of hydatid cyst. The course of the disease can be silent in most patients until a complication occurs or raise the size of cyst a huge amount . Composition of clinical history, family history, physical examination, serological and immunological studies direct definitive diagnosis. The most used diagnostic method for differential diagnosis is abdominal ultrasound (USG). Abdominal tomography (CT) or magnetic resonance imaging (MRI) are used for advanced diagnosis. The most used diagnostic method for differential diagnosis is abdominal ultrasound (USG). Abdominal tomography (CT) or magnetic resonance imaging (MRI) are used for advanced diagnosis. There are lots of techniques can be used for treatment such as medical treatment, percutaneous aspiration and surgical removal of cyst  Life threatening complications may develop if the infection is not treated properly. Accurate diagnosis and radical surgical resection with pre and postoperative Albendazole led to a successful one. This is a case of giant hepatico peritoneal hydatid cyst involving entire left lobe of liver and extending to pelvis abutting urinary bladder with multiple omental cyst..